Many biocidic and therapeutic agents, no matter how diverse—in terms of composition or function, have limited utility for one or more of a number of factors ranging from cost to toxicity. Some agents may have toxicity concerns precluding efficacious use. Others, while perhaps safe at useful concentrations, may be cost prohibitive.
For instance, the natural antibacterial agent nisin is commonly used as a preservative in many heat-processed and low-pH foods. A fermentation product of Lactococcus lactis (formerly known as Streptococcus lactis), it is commercially produced from cultured milk or by the fermentation of other substrates. Several factors, including one or more complex polycyclic structures, preclude synthesis. Highly controlled fermentation and isolation techniques contribute to its high cost and limited utility.
On the other hand, an antimycotic agent such as natamycin, while costly, presents other issues. Toxicity and related regulatory concerns have limited application to ophthalmic suspensions (i.e., eye drops) and treatment of selective cheese products, meats, sausages, seafood and the like to prevent or reduce mold spoilage. As a fermentation product of Streptomyces natalensis and other species, it also has a complex chemical structure precluding economical, large scale synthesis.
The search for effective, economical delivery of an active agent has been an ongoing concern in the art. Likewise, the formulation of various compositions, whether or not biocidic or therapeutic, has been a subject of continued research. Various carriers, emulsifiers, and the like can aid delivery of a composition, but often do not promote performance. As a result, efforts continue toward the development of components and formulations which can enhance the benefits available from such compositions.